Combined tire pressure monitoring and keyless entry receiver

• US 20050134428A1
• Filed: 01/13/2005
• Published: 06/23/2005
• Est. Priority Date: 02/20/2001
• Status: Active Grant

• Current Assignee: Continental Automotive Systems, Inc. (Continental AG)
• Original Assignee: Siemens VDO Automotive Corporation (Siemens AG)
• Inventors: Deniau, Jean-Christophe, Desai, Tejas B., Leblanc, Melvin, O'Connor, Steve, Van Drus, Kurt, Abi-Nader, Patricia
• Granted Patent: US 7,119,661 B2
• Time in Patent Office: Days
• US Class Current: 340/5.610
• CPC Class Codes: B60C 23/0416 allocating a corresponding wheel position on vehicle, e.g. front/left or rear/right
• CPC Class Codes: B60C 23/0433 Radio signals
• CPC Class Codes: B60C 23/0464 to avoid signal interference
• CPC Class Codes: B60C 23/0466 with signals sent by transmitters mounted on adjacent vehicles
• CPC Class Codes: B60C 23/0494 Valve stem attachments positioned inside the tyre chamber
• CPC Class Codes: G07C 2009/00404 starting with prompting the lock
• CPC Class Codes: G07C 2009/00793 by Hertzian waves
• CPC Class Codes: G07C 9/00182 operated with unidirectional data transmission between data carrier and locks
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04L 27/0012 arrangements for identifying the type of modulation
• CPC Class Codes: H04L 27/06 Demodulator circuits; Receiver circuits
• CPC Class Codes: H04L 27/14 Demodulator circuits; Receiver circuits

Abstract

A system for monitoring conditions within a tire (12) including a sensor assembly (14) including a pressure sensor (36), an accelerometer (34), a temperature sensor (32), and a transmitter (40) to transmit signals indicative of current tire conditions. A remote transmitter (22) for actuating a remote keyless entry system (19) emits a signal to actuate a function of the keyless entry system (19) such as unlocking doors (20) of the motor vehicle (10). A receiver assembly (16) includes an amplitude shift keyed receiver (52) and a frequency shift keyed receiver (58) selectively engagable to receive radio frequency transmissions from the tire monitoring system or the remote keyless entry system (19).

Claims

1. A system for monitoring conditions within a tire comprising:

a sensor assembly disposed within each tire of a motor vehicle,

a transmitter in communication with said sensor assembly to transmit a frequency shift keyed transmission indicative of current tire conditions;

a remote transmitter for actuating a remote keyless entry system, said remote transmitter emitting an amplitude shift keyed transmission to actuate a function of said keyless entry system;

a receiver assembly for receiving said frequency shift keyed transmission signal indicative of said current tire conditions and said amplitude shift keyed transmission signal to actuate a function from said remote transmitter wherein said transmission indicative of current tire conditions includes an amplitude shift keyed wake-up signal for alerting said receiver assembly of an incoming frequency shift keyed transmission signal.

2. The system of claim 1, wherein said receiver assembly includes an amplitude shift keyed receiver, and a frequency shift keyed receiver, said amplitude shift keyed receiver and said frequency shift keyed receiver are selectively engaged to receive incoming signals in response to a predetermined triggering event.

3. The system of claim 2, wherein said predetermined triggering event is the current speed of the motor vehicle.

4. The system of claim 3, wherein said amplitude shift keyed receiver is engaged to receive incoming signals for speeds below a predetermined speed threshold of the motor vehicle and said frequency shift keyed receiver is engaged to receive incoming signals for speeds above said predetermined speed threshold.

5. The system of claim 2, wherein said amplitude shift keyed wake up single initiates a switch from said amplitude shift keyed receiver to said frequency shift keyed receiver.

6. The system of claim 1, wherein said transmitter sends said signal at predetermined intervals, said predetermined intervals varied in response to motor vehicle speed.

7. The system of claim 1, wherein said predetermined interval is greater at speeds above said predetermined speed threshold than below said predetermined speed threshold.

8. The system of claim 7, wherein said predetermined interval increases in response to variation of pressure within one of said tires.

9. The system of claim 1, wherein said transmission indicative of said tire conditions includes a plurality of data frames sent at random time intervals to prevent repeated overlap of transmissions from two or more of said sensor assemblies.

10. The system of claim 9, wherein said random time interval is transmitted to said receiver assembly such that said receiver assembly anticipates subsequent data frames of said transmission indicative of said tire condition.

11. The system of claim 10, wherein said amplitude shift keyed receiver is engaged during said random time interval.

12. The system of claim 1, wherein said receiver assembly includes a learning mode for discerning between signals from sensor assemblies disposed on other motor vehicles;

said learning mode compares an acceleration value obtained from said sensor assembly with a vehicle acceleration value to distinguish between sensor assemblies disposed on another motor vehicle.

13. A receiver assembly for receiving signals indicative of tire conditions for a tire pressure monitoring system and signals initiating activation of a specific function for a remote keyless entry system, said receiver assembly comprising;

an amplitude shift keyed receiver;

a frequency shift keyed receiver;

said receivers selectively engaged to receive incoming signals in response to a triggering event, wherein said frequency shift keyed receiver is engaged responsive to receiving an amplitude shift keyed wake-up signal from the tire pressure monitoring system.

14. The assembly of claim 13, wherein said triggering event is a predetermined speed of the motor vehicle.

15. The assembly of claim 13, wherein said tire pressure monitoring system includes a sensor assembly, said sensor assembly including a transmitter emitting a signal indicative of tire conditions, said signal is a frequency shift keyed transmission.

16. The assembly of claim 13, wherein said remote keyless entry system includes a remote transmitter, said remote transmitter emitting an amplitude shift keyed transmission.

17. The system of claim 13, wherein said amplitude shift keyed receiver is engaged to receive incoming signals for speeds below a predetermined speed threshold of a motor vehicle and said frequency shift keyed receiver is engaged to receive incoming signals for speeds above said predetermined speed threshold.

18. The system of claim 17, wherein said tire monitoring system emits a signal indicative of tire conditions and includes said amplitude shift keyed wake up signal, said amplitude shift keyed wake up signal initiating a switch from said amplitude shift keyed receiver to said frequency shift keyed receiver.

19. A method of determining a position of sensor assemblies for a tire pressure monitoring system of a motor vehicle comprising the steps of:

a. transmitting a signal indicative of tire acceleration to a receiver assembly;

b. obtaining data indicative of motor vehicle speed from a vehicle system;

C. comparing the signal indicative of tire acceleration with the data indicative of motor vehicle acceleration; and

d. recording the sensor assembly identification code in response to the signal indicative of tire acceleration being substantially equal to the data indicative of motor vehicle acceleration.

20. The method of claim 19, further including the step of relearning sensor assembly position in response to the motor vehicle remaining stationary for a predetermined period of time.

21. The method of claim 19, further including the step of recognizing a new sensor assembly in response to receiving a desired number of data indicative of tire acceleration that compare favorably with the acceleration data indicative of the speed of the motor vehicle.

22. The method of claim 19, further including the step of obtaining data that indicates that the motor vehicle is turning and correlating the data indicative of a turn of the motor vehicle to indicate the position of the sensor assembly on the motor vehicle.

23. The method of claim 19, further including the step of measuring signal strength to determine the position of said sensor assembly.